Elder Scrolls Online has tons of interesting items/item sets you can get in the game but, virtually all of them involve grinding to obtain them based on looking things up online rather than natural discovery unlike prior Elder Scrolls titles.
For example, I'm sure many of the people that played Skyrim remember getting Gloves of the Pugilist from Gian the Fist in the Ratway.
I'd suggest that the "Lootable Weaponry" not be able to be traded, researched, sold, deconstructed, upgraded, enchanted or transmuted and to have the items be of legendary quality and level up with the player. This will enable players to find good/interesting stuff they can use for extended periods of time without disrupting the economy.
Balance wise, you'd be aiming for the item to be somewhat worse than the meta options that require grinding in optimized PvP and PvE to ensure that people still gain a benefit from the grind.
ESO has boatloads of existing weapon styles for the items to draw from that many players rarely/never see.
Below are some potential examples of "Lootable Weaponry":
Solstice has a Worm Cult style of the Flame Adept NPC class unarmed npcs it could be fun if they dropped a gauntlet that could be used to help with unarmed combat.
It might be fun to find an old Corelanya staff that summons zombies or bog blights.
You could have some items on the coast/that can be fished up from the coast that might have been lost from shipwrecks.
From a more mechanic oriented perspective you could have things like a bow that granted Empower while in stealth to help replicate the gameplay style of Skyrim's stealth archer builds at lower levels, you could have items that weaken the player while equipped for people that wanted more challenging gameplay, you could add item that would potentially benefit more niche builds similar to Morrowind's Flawed Dwemer Jinksword, finally you could implement items like Morrowind's Light of Day that cause harm to players that do not align with the items design.
Having more interesting stuff to grab would also open up the possibility to have cursed items like in Morrowind where grabbing an item might summon an enemy.